Solenoid valves are often used to automatically control the flow of gas or liquid in a wide variety of applications and environments. A solenoid is generally an electromechanical device that is controlled using electricity by enabling the flow of current through a coil, which ultimately actuates a valve such as a pneumatic or hydraulic valve, or a solenoid switch. For example, an electromechanical solenoid includes an inductive coil that is wound around a movable armature. The coil is typically shaped such that the armature can be moved in and out, thereby changing the inductance of the coil as an electromagnet. The controllable motion of the armature can be used to provide a mechanical force to control, for example, gas flow through a valve. In this manner, moving the actuator through the core of a solenoid valve enables the channeling of gas or liquid to an appropriate port. Thus the valve changes state when the actuator is moved inside the core, either opening or closing a port(s) to allow a gas or liquid to flow when the actuator is in an active state. A spring or other mechanism may be used to return the actuator to a resting state upon removal of the current flow, thereby closing the port for gas or liquid flow.
Solenoid valves therefore include moveable mechanical parts that are controlled by providing the appropriate current to the valve. The current can be applied by providing a signal(s) to initiate the flow of current, which in turn enables control of the solenoid valve. However, due to the moving mechanical parts, these solenoid valves can degrade and will eventually wear out. Extending the life of such valves beneficially impacts system cost and reduces system down time.
Accordingly, there is a need for an apparatus and method for extending the mean time to failure (MTTF) for solenoid valves. The present invention fulfills these and other needs, and offers other advantages over prior art approaches.